Altered content of cytokines has been described in peritoneal fluid from patients with endometriosis (1). Cytokines associated to endometriosis, such as TNF-α (tumor necrosis factor), Macrophage Chemotactic Protein-1 (MCP), Interleukin-6 (IL), IL-8 and Chemokine receptor 1 (CCR), are present in the peripheral blood and in the peritoneal fluid (2). There is also an impact on fertility of Interferon-γ (IFN) and Tumor necrosis factor-α (TNF) facilitating ovulation and fertilization whereas IL-1β and colony stimulating factor-1 (CSF) can affect implantation (3). There are also studies on substances such as anti-TNF, which in vitro has been demonstrated to have the capacity of reversing the decreased sperm motility caused by TNF (4). Further there have also been therapeutic approaches to treat endometriosis by regulating the cytokine release such as TNF-binding protein-1 and IL-12 which have proved to be effective in reducing endometriosis lesions (5).
Lidocaine is a well known local anaesthetic of the formula
having membrane stabilizing, anti-arrhythmic and anti-inflammatory properties.
Increased amounts of leukocytes, mainly macrophages, have been found in the peritoneal fluid of women with endometriosis. The exact pathogenesis for endometriosis and the intraperitoneal leukocytosis is unknown. In this study a MCP-1 (Macrophage Chemotactic Protein) production from endometriosis cells has been found. This can contribute to the recruitment of more macrophages in to the peritoneal cavity. The MCP-1 production seems to be reduced by lidocaine. Thereby fewer macrophages might be recruited intraperitoneally and constitute a potential explanation for the clinical effect on pain due to endometriosis and dysmenorrhea. Macrophages are a major source of cytokine production.